“I said a number of things about Keira which were petty, mean and hurtful,” the director posted in a tweet on Wednesday. The two worked together on the 2013 movie musical “Begin Again,” which also starred Mark Ruffalo.

In comments recently published in the UK’s Independent, Carney said, “I’ll never make a film with supermodels again” — an apparent reference to Knightley’s gig as a Chanel spokesmodel and frequent magazine cover girl.

The apology was annotated with the message: “From a director who feels like a complete idiot.”

Carney went on to say that he also apologized to Knightley personally and that he wanted to issue the public version to the actress’ friends, fans and anyone else he may have offended. “It’s not something I could ever justify, and will never repeat.”

Lorene Scafaria (“Seeking a Friend for the End of the World”) also offered praise. “I agree with Mark. Keira was a joy to work w/. Present & easy & really, really good at her job. Just lovely,” she tweeted.

In the Independent interview, Carney said of the two-time Oscar nominee, “I don’t want to rubbish Keira, but you know it’s hard being a film actor and it requires a certain level of honesty and self-analysis that I don’t think she’s ready for yet and I certainly don’t think she was ready for on that film.”

Carney said he became “disenchanted” during the production of “Begin Again” in the United States. “Not that I didn’t enjoy ‘Begin Again,’ but Keira has an entourage that follow her everywhere so it’s very hard to get any real work done,” he said, adding that he yearned to return to Ireland to “make films that nobody cared about.”

According to Carney, Knightley’s “real problem” was that she didn’t sing or play guitar. “It’s very hard to make music seem real if it’s not with musicians. And I think the audience struggled a little bit with that in ‘Begin Again.'”

He said he tried his best to work with what he had, but that, ultimately, Knightley wasn’t convincing as a singer-songwriter. “I really wanted to work with musicians and actors that could play their instruments properly and sing.”

Carney saved the praise for his male “Begin Again” stars. He called Mark Ruffalo “fantastic” and said Adam Levine was “a joy to work with.”

He took more jabs at Knightley, too: “Keira’s thing is to hide who you are and I don’t think you can be an actor and do that. … It’s not like I hate the Hollywood thing but I like to work with curious, proper film actors as opposed to movie stars.”

Regarding the stellar reviews “Sing Street” has received, Carney said, “I’m very surprised; it’s a small personal movie with no Keira Knightleys in it.”

Ethan Hawke plays a drone-controlling air force officer in "Good Kill," and reportedly proved as generous on the press line as he did at the Storys after party on Tuesday night for the Voltage Pictures film from Andrew Niccol.